Experimental and modeling studies on the effects of temperature, pressure and brine salinity on interfacial tension in live oil-brine systems

Interfacial tension (IFT) is a key parameter which affects the remaining oil in place and fluid distributions in an oil reservoir. Mobilization of trapped oil in a reservoir after primary and secondary recovery schemes, as part of a tertiary oil recovery, requires a true and accurate understanding of interfacial interactions between oil, brine and reservoir rock. This study presents an investigation of temperature, pressure and synthetic formation water salinity effects on interfacial tension of two carbonate oil reservoirs. A pendant drop instrument was used to perform the measurements. In addition, Least Square Support Vector Machine (LS-SVM) in combination with Coupled Simulated Annealing (CSA) was used to model the values of IFT. Results show that the IFT of reservoir A increases with increasing temperature, pressure and salinity of synthetic formation water and the IFT data for reservoir B increases with increasing pressure and salinity of synthetic formation water but decreases with increasing pressure. The results of modeling studies show that the developed model is accurate for prediction of experimental IFT data. (C) 2016 Elsevier B.V. All rights reserved.